Envelope processing machine



y 1957 o. P. WELSH 2,800,841

ENVELOPE PROCESSING MACHINE Filed Feb. 16. 1954 2 Sheets-Sheet 1.

IN V EN TOR.

July 30, 1957 o. P. WELSH 2,800,841

ENVELOPE PROCESSING MACHINE Filed Feb. 16. 1954 2 Sheets-Sheet 2 IN V EN TOR.

U iteti States Patent ENVELOPE PROCESSING MACHINE ()rmonde P. Welsh, Minneapolis, Minn., assignor to Parten Machinery Company, Minneapolis, Minn., a partnership Application February 16, 1954, Serial No. 410,630

12 Claims. (Cl. 93-62) The present invention relates to a novel apparatus for processing envelope blanks automatically and at high speeds.

An object of the present invention is to provide a novel apparatus for folding flaps of envelope blanks and, more particularly, for folding bottom and seal flaps of the blanks while the blanks are continuously fed through the apparatus at high speeds.

Another object of the present invention is to provide a novel apparatus forcontinuously feeding envelope blanks from bottom flap folding means and reversing the leading and trailing relationship of the envelope blank bottom and seal flaps to arrange the seal flap at the leading edge for presentation to seal flap folding means.

A further object of the present invention is to provide an apparatus as set forth in the preceding paragraph which is capable of high speed operation while arranging the blanks in predetermined relationship with respect to the seal flap folding means whereby the seal flaps may be rapidly and properly folded.

Other objects and advantages of the present invention will become apparent from the following description and accompanying drawings wherein:

Fig. 1 is a somewhat diagrammatic side elevational view of an apparatus embodying the principles of this invention;

Fig. 2. is a plan view of an envelope blank which may be processed by the apparatus of this invention;

Fig. 3 is a fragmentary end elevational view taken along line 3-3 in Fig. 1;

Fig. 4 is an enlarged fragmentary view which is partially in cross section along line 4--4 in Fig. 1; and

Fig. 5 is an enlarged fragmentary side elevational. view similar to Fig. 1 but showing a slightly modified form of the present invention.

Referring now more specifically to the drawings wherein like parts are designated by the same numerals throughout the various figures, an apparatus embodying the principles of this invention includes a mechanism 12 for applying glue to the bottom flap of an envelope blank, means 14 for folding the bottom flap, means 16 for folding the seal flap of the envelope, means 18 for transferring the envelope blank from the bottom flap folding means to the seal flap folding means, and means 20 for receiving and stacking the finished envelopes.

In Fig. 2, there is illustrated an envelope blank 22 of the type which may be processed by the apparatus of this invention. The envelope blank includes a body portion 24, side or end flaps 26 and 28, a bottom flap 30 and a seal flap 32. It is understood that the apparatus 10 illustrated and described herein forms a part of a structure for not only folding the bottom end seal flaps but also capable of applying glue to the seal flap and of folding the side flaps against the body of the envelope. In general, the entire structure includes, in addition to the apparatus 10, means for feeding envelope blanks from a supply stack, means for applying to and drying glue on the seal flaps of the blanks and means for folding the side flaps from which last mentioned means the blanks are directed to the apparatus 10. Since these means form no part of the present invention, they are not illustrated in the drawings and will not be described in detail.

The envelope blanks are fed from the above mentioned side or end flap folding means to the glue applying mechanism 12 by a pair of feed rollers 34 and 36. The glue applying mechanism includes a roller 38 carrying rubber glue applying dies 40 and 42 which are shaped to apply glue to the margins of the envelope blank bottom flaps 30. Any suitable means, not shown, may be provided for supplying glue to the dies 40 and 42 and a back-up or impression roller 44 is disposed to cooperate with the glue applying dies 40 and 42. As the envelope blanks leave the glue applying roller, they are picked up and fed by rollers 46 and 48 to the bottom flap folding mechanism 14.

The envelope blanks are fed to the folding means 14 with the bottom flaps providing the leading edge of the blanks. A suction roller 50 having a suction gripper 52 grips the leading bottom flap 30 and pulls it upwardly, as shown in Fig. 1. At the same time, a suction roller 54 having ports 56 and 58 grips the body portion of the envelope blank and pulls it downwardly. Preferably, the gripper 52 engages the forward edge of the bottom flap while the suction port 56 engages the body of the blank adjacent the bottom flap bend line 60 to facilitate proper folding of the flap. As the rollers 50 and 54 continue to rotate past the positions shown in Fig. 1, the gripper 52 is caused to release the bottom flap by the means described below and the suction wheel 54 bends and carries the blank downwardly beneath a bending or folding roller 62 so that the bottom flap is folded toward the body portion of the blank. Preferably, the roller 62 is spaced from the periphery of the roller 54 so that the bottom flap is initially folded along the line 60 without being creased to prevent premature and improper creasing. Furthermore, the roller 62 is connected with and driven by a friction roller 64 which engages the periphery of the roller 54 beyond the end of the bottom flap to eliminate any frictional drag between the roller 62 and the bottom flap that might pull the envelope blank away from the suction port 56 or cause relative movement between the blank and the suction roller 54. In order to finally crease the bottom flap along the line 60 and to firmly press the glued portions or margins of the bottom flap against the previously folded side flaps 26 and 28, a pressure roller 66 is provided.

Referring particularly to Fig. 4, it is seen that the bottom flap gripping suction roller 50 is fixed on a rotatable shaft 68. The shaft is drilled to provide a passage way 70 communicating with the gripper 52 and connected with a suction line 72 through valve means 74. The suction line 72 is adapted to be connected to any suitable suction chamber, not shown. The valve means 74 includes a flange 76 fixed on the shaft by means of a set screw 78 and provided with a passageway 80. A valve body 82 surrounds the shaft 68 and is held against rotation by a bracket arm 84. The valve body is connected to the conduit or hose 72 and is provided with an elongated arcuate opening 86 (see Fig. 1), which intermittently communicates with the passageway in the rotating flange 76, thereby intermittently applying suction to the gripper 52. As shown best in Fig. 1, the arcuate opening 86 is located to apply suction to the gripper 52 in a manner to grip the forward marginal edge of an envelope blank entering between the rollers 50 and 54 and to cut oif the suction after the roller 50 has rotated about one-quarter of a revolution. In order to prevent air leakage between the flange 76 and the valve body 82, the body is resiliently urged against the flange by means of a compression spring 88 acting between the valve body and a thrust ring 90 fixed on the shaft 68.

Suction is also intermittently applied to the ports 56 and 58 on the roller 54 so that the envelope blank is properly gripped and then released after the folding operation is completed. This is accomplished by rotatably mounting the roller 54 on a fixed hollow shaft 92, which shaft is connected to a suitable source of vacuum, not shown. The port 56, which is provided by a hollow block 94, is intermittently connected with the bore of the shaft 92 through an arcuate opening 96 in the shaft. In order to accomplish this, the block 94 which, of course, rotates with the roller 54 receives a tube 97 telescoping within a tube 98. The inner end of the tube 98 is mounted within a block 100, having a bore therethrough, which block slidably engages the fixed shaft 92 and is yieldably pressed thereagainst by a compression spring 102. The port 58 is provided with identical means for intermittently connecting it with the arcuate opening or slot in the shaft 92.

In accordance with the present invention, the envelope blanks are continuously fed from the bottom flap folding means 14 to the seal fiap folding means 16 in a manner so that the original leading and trailing positions of the bottom and seal flaps are reversed and the seal flap occupies the leading position when the blank is introduced into the seal flap folding means. This is accomplished by the mechanism 18 which includes a guide 104 for directing the blanks emerging from between the suction and pressure rollers 54 and 66 respectively to endless feed belts 106 and 108. The belt 106 encircles rollers 110 and 112 and an idler roller 114. In addition, the belt 106 is engaged by a tensioning roller '116 carried by an arm of a bracket 118 mounted on a fixed shaft 120. The above mentioned guide 104 may also be mounted on another arm of this bracket and the roller 114 is carried by still another bracket arm. The feed belt 108 is wrapped around a drive roller 122 and a roller 124 which is carried by an adjustable bracket 126 mounted on a fixed shaft 128. The envelope blanks are engaged by the belts between the rollers 110 and 122 and fed downwardly toward a pair of feed chains 130 having generally horizontally disposed upper courses. The feed chains encircle sprockets 132, 134 and 136 and are driven in a clockwise direction as viewed in Fig. 1. It should be noted that the roller 124 is positioned so that the feed belt 108 is also partially wrapped around the idler roller 114 whereby the direction of downward movement of the envelope blanks is changed so that the blanks are directed generally horizontally over the feed chains 130 and in a direction opposite to the direction of movement of the chains. Each of the feed chains carries a series of spaced dogs 138 which pick up the blanks deposited on the chains and feed the blanks toward the seal flap folding mechanism.

Means is provided for positively positioning the blanks emerging from between the feed belts 106 and 108 to insure proper registration of the blanks with the feed dogs on the chains 130. In the embodiment shown in Figs. 1 and 3, this means includes a pair of stop members 140 which are mounted on opposite sides 142 and 144 of the apparatus frame. In addition, the pressure roller 146 carried by a resilient bracket arm 148 is yieldably urged upwardly against the feed belt 106. The bracket arm 148 is fixed in any suitable manner on a transverse bar 150. It is understood that the blanks emerging from between feed belts 106 and 108 are traveling at high speeds and they are thrown rearwardly of the chains 130 so that they enter between the pressure roller 146 and the feed belt 106. With frictional engagement between the blanks and the feed belt 106 thus maintained, the blanks are advanced by the belt 106 rearwardly over the feed chains 130 until they engage the stops 140. At this point, movement of the blanks is momentarily arrested, whereupon they are engaged and fed by the dogs 138.

In Fig. 5, there is illustrated a slightly modified form of the mechanism for positioning the blanks relative to 2,soo,s41 v the feed chain dogs. In this embodiment, the above described pressure roller 146 and resilient bracket arm 148 have been replaced by a similar pressure roller 152 carried by a member 154 slidably mounted on a bracket 156. The lower end of the slide member 154 carries a cam follower 158 which rides upon a rotatable cam 160. A spring 162 is connected between a pin 164 on the bracket 156 and a pin 166 on the slide member for maintaining the cam follower in engagement with the cam. The high portions of the cam are shaped so that the roller 152 is pressed against the feed belt 106. Thus, the embodiment of Fig. 5 functions in substantially the same manner as the embodiment of Figs. 1 and 3 to feed the envelope blanks rearwardly against the stop 140. However, when a blank has been located against the stops 140 and has been engaged by a feed dog, the cam follower 158 drops to a low portion of the cam, permitting the roller 152 to drop away from the feed belt 106, whereby the blank may move with the feed dogs without interference from the roller 152.

As set forth hereinabove, the envelope blanks are fed from the mechanism 18 with their seal flaps in the leading position to the seal flap folding means 16. The seal flap folding means includes a suction wheel 168 having a suction gripper 170 for gripping the forward edge of the seal flap. The body portion of the envelope blank is also gripped by a suction wheel or roller 172. The suction rollers 168and 172 are respectively substantially identical to the above described suction rollers 50 and 54 and, therefore, the details of these rollers need not be repeated. As the envelope blank is carried around the suction roller 172, the seal flap is first bent outwardly by the suction roller 168 in the manner illustrated in Fig. l and then pressed against the body of the envelope blank by a pressure roller 174. After the seal flaps have been folded, the completed envelope blanks are fed upwardly and stacked on a generally horizontally disposed platform 176. The feeding and stacking means for accomplishing this includes feed belts 178 and 180. The belts 178 are wrapped around the suction roller 172 on opposite sides of its suction ports and also around idler rollers 182 and 184. The roller'182 is carried by an arm 186 of a bracket 188 and the roller 184 is carried by an arm 190 pivotally mounted on the bracket. Spring means 192 is provided for biasing the pivoted arm 190 in a manner to maintain the proper tension in the belt 178. Feed belts are wrapped around a drive roller 194, the pressure roller 174 and an idler roller 196. Thus, as the envelope blanks are carried around the suction roller 172, they are inserted between the feed belts 178 and 180 and are advanced upwardly to a position above the horizontal platform 176. An oscillating pusher blade 198, mounted on a rock shaft 200, is provided for engaging the blanks emerging from between the feed belts 1-78 and '180 and pressing the blanks against a stack 202 supported on the platform. In order to prevent the endmost blank from falling from the platform during the rearward movement of the pusher blade 198, an oscillating catch member 204, mounted on a rock shaft 206, is provided. The catch member has an upwardly extending finger 208 adapted to extend above the platform 176 and engage the endmost blank while the pusher blade moves to and from the broken line position shown in Fig. 1. As the pusher blade moves to the solid line position shown in Fig. l, the member 204 is moved downwardly so that the finger 208 will not interfere with the blank being added to the stack.

The operation of the apparatus of this invention is fully set forth in the preceding descriptive matter and, therefore, will not be repeated. However, it is understood that the various elements of the apparatus are driven in timed relationship with respect to each other in order to function in the manner set forth. While the drive means for the apparatus has not been illustrated, it is obvious that any well known devices, such as gears, drive belts or chains may be provided for driving the various elements of the apparatus including the feed rollers, suction rollers, pressure rollers, feed belts and feed chains. In addition, it is obvious that any suitable cam means may be provided for oscillating the rock shafts 200 and 206 in proper timed relationship.

From the above description, it is seen that the present invention has provided an apparatus which is capable of folding the bottom and seal flaps of envelopes at relatively high speeds while the envelope blanks are continuously advanced through the apparatus. More specifically, it is seen that the present invention has provided a novel apparatus for continuously feeding envelope blanks from bottom flap folding means to seal flap folding means at high speeds while reversing the leading and trailing positions of the bottom and seal flaps.

While the preferred embodiments of the present invention have been shown and described herein, it is obvious that many structural details may be changed without departing from the spirit and scope of the appended claims.

The invention is claimed as follows:

1. In an envelope processing apparatus having bottom flap folding means and seal flap folding means, means for feeding envelope blanks from the bottom flap folding means to the seal flap folding means and for reversing the positions of the leading and trailing edges of the blanks to arrange the seal flap as the leading edges, said feeding means comprising a pair of endless members for holding blanks therebetween and feeding the blanks in one direction from the bottom flap folding means, fixed stop means for limitingmovement of the blanks in said one direction, endless conveyor means moving in the opposite direction, said endless conveyor means having members disposed thereon for positively engaging blanks located by said stop means and feeding the blanks along a predetermined path of travel toward said seal flap folding means, said endless conveyor means being disposed at a side of said path of travel opposite from said endless members, and means for feeding and holding blanks against said stop means, said feeding and holding means including one of said endless members and means spaced from the other of said endless members and disposed at the same side of said path of travel as said endless conveyor means for maintaining the blanks in frictional contact with said one endless member.

2. An apparatus as defined in claim 1 wherein said last named means is operable to release a blank substantially when the blank is engaged by a feeding member on said conveyor means.

3. An apparatus as defined in claim 1 wherein said last named means comprises a roller yieldably biased against said one endless member.

4. An apparatus as defined in claim 1 wherein said endless members are provided by endless belts, and wherein the endless belts are of different lengths to permit the blanks to pass into engagement with said conveyor means while maintaining frictional engagement with saidone endless member.

5. In an envelope processing apparatus having bottom flap folding means and seal flap folding means, means for feeding envelope blanks from the bottom flap folding means to the seal flap folding means and for reversing the positions of the leading and trailing edges of the blanks to arrange the seal flaps as the leading edges, said feeding means comprising a pair of endless belts having adjacent courses for holding and feeding blank-s therebetween in one direction from the bottom flap folding means, said adjacent courses having portions moving generally horizontally, endless conveyor means disposed beneath said endless belts and moving in the opposite direction for receiving blanks from the endless belts and feeding the blanks along a predetermined path of travel toward the seal flap folding means, stop means disposed between said course portion of the upper endless member and said endless conveyor means for engaging leading edges of the blanks moving in said one direction for positively positioning the blanks, and means on said endless conveyor means for positively engaging said edges positioned by said stop means for feeding the blanks in the opposite direction, said horizontally moving portion of the upper endless belt being longer than the horizontally moving portion of the lower endless belt for engagement with the blanks while the blanks are deposited on said conveyor means, and means disposed at the same side of said path of travel as said endless conveyor means for maintaining the blanks in frictional engagement with said longer endless belt portion to insure feeding of the blanks against said stop means.

6. An apparatus as defined in claim 5 wherein said last named means includes a roller yieldably biased against said horizontally moving portion of the upper endless belt and spaced from the lower endless belt to maintain the blanks in frictional contact with the upper endless belt until the blanks have moved into predetermined registration with the endless conveyor means.

7. An apparatus for processing envelope blanks comprising means for folding bottom flaps of the blanks, means for folding seal flaps of the blanks, means for feeding blanks from said bottom flap folding means to said seal flap folding means and for reversing the leading and trailing positions of the bottom and seal flaps to arrange the seal flaps in the leading position for presentation to the seal fiap folding means while moving along a predetermined path of travel, said seal flap folding means comprising a suction roller disposed at one side of said path of travel for gripping a body portion of the blanks, means at an opposite side of said path of travel for gripping and partially folding the seal flaps, endless belt means disposed at said one side of said path of travel and Wrapped around said suction roller, and a second endless belt means adjacent and opposed to said first mentioned endless belt means and disposed at said opposite side of said path of travel for completing the folding of said seal flaps, said endless belt means having cooperating portions extending away from said suction roller to convey the blanks to a point of discharge.

8. An apparatus as defined in claim 7 wherein said means for gripping the seal flaps comprises a second suction roller.

9. An apparatus for processing envelope blanks comprising means for feeding the blanks along a predetermined path of travel with seal flaps of the blanks in a leading position, a suction roller disposed at one side of said path of travel for gripping a body portion of the blanks, means at an opposite side of said path of travel for gripping and partially folding the seal flaps, endless belt means at said one side of said path of travel and wrapped around said suction roller, and a second endless belt means adjacent said first mentioned endless belt means and at said opposite side of said path of travel for completing the folding of said seal flaps, said endless belt means having cooperating portions extending away from said suction roller to convey the blanks to a point of discharge.

10. An apparatus for processing envelope blanks having flaps to be folded comprising means for feeding the blanks with said flaps in a leading position, a suction roller for gripping a body portion of blanks, means for gripping and partially folding the flaps of blanks held by said suction roller, a driven pressure roller adjacent to and spaced from said suction roller for further and incompletely folding said flaps, and a driven pressure roller acting against said suction roller for completing the folding of said flaps.

11. An apparatus as defined in claim 10 wherein said flaps are the bottom flaps of envelope blanks, which apparatus includes means for folding seal flaps of said blanks, and means for feeding the blanks having folded bottom flaps from said suction wheel to said seal flap folding means and for reversing the leading and trailing positions of said bottom and seal flaps of the blanks to arrange the seal flaps in the leading position for presentalion to the seal flap folding means while movin along a predetermined path of travel.

12. An apparatus as defined in claim 11 wherein said seal flap folding means comprises a suction roller disposed at one side of said path of travel for gripping a body portion of the blanks, means disposed at an opposite side of said path of travel for gripping and partially folding the seal flaps, endless belt means disposed at said 10 one side of said path of travel and wrapped around said last mentioned suction roller, and a second endless belt means adjacent said first mentioned endless belt means and disposed at said opposite side of said path of travel for completing the folding of said seal flaps, said endless belt means having cooperating portions extending away from said last mentioned suction roller to convey the blanks to a point of discharge.

References Cited in the file of this patent UNITED STATES PATENTS 1,519,439 Cheetham Dec. 16, 1924 1,884,468 Winkler et a1. Oct. 25, 1932 2,047,710 Schwartz July 14, 1936 2,109,050 Quick et a1. Feb. 22, 1938 2,163,037 Heywood June 20, 1939 2,163,038 Heywood June 20, 1939 2,287,719 Beasley June 23, 1942 2,307,907 Becker Jan. 12, 1943 15 2,312,162 Heywood Feb. 23, 1943 2,568,604 Bechberger Sept. 18, 1951 

